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1.
Signaled avoidance was studied in individual honeybees that visited the laboratory regularly to take sucrose solution from a target set on the sill of an open window. During feeding, substrate vibration or airstream was used to signal a brief shock that could be avoided by breaking off contact with the food for a few seconds. Aversive conditioning of the context was measured in terms of return time (the time between successive visits). In Experiment 1, experience with unsignaled shock was found to lengthen return time—which experience with signaled shock did not—and to impair performance in subsequent avoidance training with signaled shock (the US-preexposure effect). In Experiment 2, experience with unsignaled shock given after signaled avoidance training lengthened return time but had no effect on response to the signal in a subsequent extinction test. These results closely resemble the results obtained in analogous experiments with vertebrates. 相似文献
2.
In a series of four experiments with free-flying honeybees, individual foragers were trained with targets of two different colors that contained 5 or 20 μl of 50% sucrose solution. The two targets were singly presented in quasi-random sequences on each visit, with the amount of reward to be found on each target perfectly predictable from its color. The number of training visits (4–32) was varied both within and between experiments, and so also was the relative frequency of trials with the 5- and 20-μl targets (1:1, 2:1, 3:1, and 9:1). At the conclusion of training under each condition, unrewarded responses to the targets were measured in a 10-min extinction test, with the targets presented either separately to two different groups of animals (Experiment 1) or as a pair (Experiments 2–4). When the number of training trials with each target was the same (Experiments 1 and 2), the animals responded more in extinction to the 20-μl target than to the 5-μl target, although there was a decline in the overall level of responding to both targets (an overlearning-extinction effect) as the number of training trials increased. After nine times as many, or only three times as many, training trials with the5- μl target as with the 20-μl target, the animals responded more in extinction to the 5-μl target (Experiment 3); after twice as many training trials with the 5-μl target as with the 20-μl target, there was equal responding to both (Experiment 4). The preferences shown in the choice tests of Experiments 2–4 could be simulated rather accurately on the assumptions of a model previously developed to deal with the discrete-trials choice behavior of honeybees and the further assumption that associative strength grows at a rate increasing with amount of reward to an asymptote independent of amount of reward. 相似文献
3.
Four conditioned suppression experiments with rats, using an ABC renewal design, investigated the effects of compounding the target conditioned excitor with additional, nontarget conditioned excitors during extinction. Experiment 1 showed stronger extinction, as evidenced by less renewal, when the target excitor was extinguished in compound with a second excitor, relative to when it was extinguished with associatively neutral stimuli. Critically, this deepened extinction effect was attenuated (i.e., more renewal occurred) when a third excitor was added during extinction training. This novel demonstration contradicts the predictions of associative learning models based on total error reduction, but it is explicable in terms of a counteraction effect within the framework of the extended comparator hypothesis. The attenuated deepened extinction effect was replicated in Experiments 2a and 3, which also showed that pretraining consisting of weakening the association between the two additional excitors (Experiments 2a and 2b) or weakening the association between one of the additional excitors and the unconditioned stimulus (Experiment 3) attenuated the counteraction effect, thereby resulting in a decrease in responding to the target excitor. These results suggest that more than simple total error reduction determines responding after extinction. 相似文献
4.
Four experiments with rat subjects examined the role of context during the extinction of instrumental (free-operant) behavior. In all experiments, leverpressing was first reinforced on a variable-interval 30-s schedule and then extinguished before being tested in the extinction and renewal contexts. The results identified three important variables affecting the renewal effect after instrumental extinction. First, ABA and ABC forms of renewal were strengthened by increasing the amount of acquisition training. This suggests that the strength of the association learned during acquisition, or the final level of performance, influences the degree of renewal after extinction. The effect of the amount of training was modulated by the second factor, the degrees of generalization from the acquisition and extinction contexts to the test context. The third variable was acquisition training in multiple contexts, which was shown to strengthen ABC renewal. Methodological, theoretical, and practical implications are discussed. 相似文献
5.
Robert A. Rescorla 《Learning & behavior》1996,24(1):11-18
Four experiments explored the increase in an instrumental response (R) with time after it had been subjected either to extinction or to training with a second outcome (O). Experiment 1 found less performance of an extinguished response immediately after extinction than after a 7-day delay (spontaneous recovery). Experiments 2–4 found a similar difference when training with a second outcome replaced extinction, despite the failure of that replacement to itself undermine performance. Similar results did not occur when the second outcome was identical to that used in initial training. These results suggest that training with a novel outcome generates a decremental process that is not directly observable but that dissipates with time. 相似文献
6.
Performance was studied during extinction after training on a homogeneous chain FR 7-FR 7, with a tandem FR 7-FR 7 as control, eight pigeons per group. During extinction, disruption of the chain was considerably greater in the first than in the second component, while tandem controls showed no differential disruption. 相似文献
7.
In the present experiments, we investigated the effects of mindfulness on behavioral extinction and resurgence. Participants received instrumental training; either they received FI training (Experiment 1), or they were trained to emit high rates and low rates of response via exposure to a multiple VR yoked-VI schedule prior to exposure to a multiple FI FI schedule in order to alter their rates of responding learned during Experiment 2. Participants were then exposed to either a focused- (mindfulness) or an unfocused-attention induction task. All participants were finally exposed to an extinction schedule in order to determine whether a mindfulness induction task presented immediately prior to extinction training affected extinction (Experiment 1) and behavioral resurgence (Experiment 2). During the extinction phase, the rates of responding were higher in the control group than in the mindfulness group, indicating that the mindfulness group was more sensitive to the contingencies and, thus, their prior performance extinguished more readily (Experiment 1). Moreover, rates of response in the extinction components less precisely reflected previous training in the mindfulness group, suggesting less resurgence of past behaviors after the mindfulness induction (Experiment 2). 相似文献
8.
In Experiment I rats were trained for 21÷2 days under partial (PRF) or continuous reinforcement (CRF) conditions starting at 18, 22, 28, or 36 days of age and were then subjected to immediate extinction. At all ages there was a strong partial reinforcement extinction effect (PREE), and absolute size of PREE was greatest in the youngest rats. Rate of extinction increased as a function of age following both CRF and PRF. In Experiment II the youngest and oldest age groups of Experiment I were run under the two reward conditions of Experiment I and in a third condition, PRF with number of rewards rather than trials equated to CRF (PRF-R). The PRF-R and PRF groups were not different in extinction, and both were more persistent than CRF. The youngest rats were again more persistent than the oldest, particularly after PRF training. In Experiment III it was shown that the well-known paradoxical effect, greater reward in CRF acquisition leads to faster extinction, operates in our youngest and oldest animals, but is more pronounced in the oldest. The results are discussed in terms of whether they require different explanations than those often applied to extinction data from adult rats. 相似文献
9.
Resurgence is the recurrence of a previously reinforced and then extinguished behavior induced by the extinction of another more recently reinforced behavior. Resurgence provides insight into behavioral processes relevant to treatment relapse of a range of problem behaviors. Resurgence is typically studied across three phases: (1) reinforcement of a target response, (2) extinction of the target and concurrent reinforcement of an alternative response, and (3) extinction of the alternative response, resulting in the recurrence of target responding. Because each phase typically occurs successively and spans multiple sessions, extended time frames separate the training and resurgence of target responding. This study assessed resurgence more dynamically and throughout ongoing training in 6 pigeons. Baseline entailed 50-s trials of a free-operant psychophysical procedure, resembling Phases 1 and 2 of typical resurgence procedures. During the first 25 s, we reinforced target (left-key) responding but not alternative (right-key) responding; contingencies reversed during the second 25 s. Target and alternative responding followed the baseline reinforcement contingencies, with alternative responding replacing target responding across the 50 s. We observed resurgence of target responding during signaled and unsignaled probes that extended trial durations an additional 100 s in extinction. Furthermore, resurgence was greater and/or sooner when probes were signaled, suggesting an important role of discriminating transitions to extinction in resurgence. The data were well described by an extension of a stimulus-control model of discrimination that assumes resurgence is the result of generalization of obtained reinforcers across space and time. Therefore, the present findings introduce novel methods and quantitative analyses for assessing behavioral processes underlying resurgence. 相似文献
10.
Water-deprived rats were used to investigate the effects of training a CS in more than one context on conditioned lick suppression. In each experiment, partial reinforcement of the CS was intermingled with unsignaled presentations of the US. In Experiment 1, subjects were either trained in one context alone, trained consecutively in two contexts (such that all training in one context occurred prior to any training in the second context), or trained alternately in two contexts. Following training, the first context, the second context, or neither context was extinguished. Testing of the CS occurred in a third (neutral) context. To the extent that either training context became established as a comparator stimulus for the CS, the comparator hypothesis (Miller & Matzel, 1988) predicts an increase in excitatory responding to the CS following extinction of that context. Subjects trained in a single context exhibited appreciable fear of the CS only when the CS’s training context had been extinguished. Additionally, subjects trained consecutively in the two contexts showed increased fear of the CS following extinction of the second, but not the first training context (i.e., a recency effect). Subjects trained alternately in the two contexts showed no increased fear of the CS as a result of either context alone being extinguished. In Experiment 2, subjects trained alternately in two contexts showed increased fear of the CS only when both training contexts were extinguished, suggesting that both training contexts had become comparator stimuli. These data indicate that multiple training contexts can either compete or act synergistic-ally in modulating responding to a Pavlovian trained CS as a function of the order of training in the different contexts. 相似文献
11.
Contrast in consummatory behavior was investigated following repeated shifts from 32% to 4% sucrose. In Experiment 1, contrast in licking and in open-field measures of activity occurred following the second and third downshifts. In Experiments 2a and 2b, equivalent contrast effects occurred following the first and second downshifts in sucrose. In Experiment 3, negative contrast remained unabated following nine downshifts in animals shifted between 32% and 4% sucrose on alternate days. Similar results were found for five downshifts in animals shifted every 2 days. In both of these latter conditions, positive contrast occurred over the first few shifts and was then lost as the 32% control group reached asymptote. These data show that repeated negative contrast effects in consummatory behavior are robust and enduring and occur under several different sets of experimental parameters. The results are discussed in terms of reinforcement level and emotional interpretations of contrast effects, and the possibility was suggested that the causal mechanism of contrast changes with repeated shifts. 相似文献
12.
It has been reported previously that rats prefer a flavor they consumed under high deprivation to a flavor they consumed under low deprivation (Revusky, 1967). Here it was found that this preference occurs only if nutritive solutions are used and the flavors are given preceding and following eating. If flavors are given separately from the daily feeding, rats prefer the flavor given under low deprivation, whether or not a nutritive solution is used (Experiment 3). If flavors are given before and after the daily feeding, rats prefer the flavor they had under high deprivation (before feeding) more if sucrose solutions are used than if saccharin solutions are used and more on a high-deprivation test than on a low-deprivation test (Experiments 1 and 2). It was concluded that the “incentive value” of consumption is not necessarily higher under high deprivation than under low deprivation. The preference for the low-deprivation flavor obtained here may reflect a greater proportional rewarding effect of consumption under low deprivation or may reflect an aversion to the flavor consumed under high deprivation. Perhaps a small taste of flavor under high deprivation initiates responses of digestion that are unsatisfied and thus aversive, and the more so the higher the deprivation level. 相似文献
13.
This study is focused on the relationship between the development of segmental awareness and dyslexia. More specifically we have tried to address the question, is it possible to learn to segment well and yet continue to read and write poorly? For this purpose, 14 second and third grade dyslexic children were assigned to three different training programs. Those who participated in the first two programs were taught the skills required to use the phonemes, while those in the third program, who served as a pseudo-control group, were given the exercises in perceptual and psychomotor activities. After the training program, children who had received the first two training programs reached a level of performance similar to that of normal readers in different tasks of segmentation of phonemes. The improvements observed in these tasks were correlated in dictation but not in reading, where there was no difference after training. 相似文献
14.
Hungry rats were trained to press a lever for food pellets prior to an assessment of the effect of a shift in their motivational state on instrumental performance in extinction. The first study replicated the finding that a reduction in the level of food deprivation has no detectable effect on extinction performance unless the animals receive prior experience with the food pellets in the nondeprived state (Balleine, 1992; Balleine & Dickinson, 1994). When tested in the nondeprived state, only animals that were reexposed to the food pellets in this state between training and testing showed a reduction in the level of pressing during the extinction test relative to animals tested in the deprived state. The magnitude of this reexposure effect depended, however, on the amount of instrumental training. Following more extended instrumental training, extinction performance was unaffected by reexposure to the food pellets in the nondeprived state whether or not the animals were food deprived at the time of testing. A second study demonstrated that the resistance to the reexposure treatment engendered by overtraining was due to the animals’ increased experience of the food pellets in the deprived state during training rather than to the more extensive exposure to the instrumental contingency. In contrast to the results of the first two experiments, however, a reliable reexposure effect was detected after overtraining in a final study, in which the animals were given greater reexposure to the food pellets in the nondeprived state. 相似文献
15.
After one-way avoidance training, rats were exposed, during avoidance response prevention, to light (CS-only) presentations or to light-shock (CS-US) pairings. Subgroups were then given 1, 5, or 10 trials during which they could escape immediately (unrestricted) or after 5 sec (restricted) by means of the previously conditioned avoidance response from a simultaneous light-shock compound. All animals were then exposed to avoidance extinction. The number of unrestricted escapes increased responding for CS-only animals, but had no significant effect on the performance of CS-US animals. Nevertheless, resistance to extinction was considerably less for CS-only animals given 10 unrestricted escapes than for CS-US animals given one unrestricted escape. One restricted escape had no more effect than one unrestricted escape for either response-prevention group. However, 5 restricted escapes elevated responding for CS-only animals to the level of CS-US animals. Extinction responding for CS-US animals increased significantly only after 10 restricted escapes. Since CS-only animals showed no further increase, resistance to extinction once more was greater for CS-US animals. These results, together with the very brief unrestricted escape latencies of CS-only animals, support a greater role for Pavlovian extinction than for response competition in the facilitation of avoidance extinction by CS-only response prevention. The fact that 10 restricted escapes were required to elevate resistance to extinction for CS-US animals over that obtained with one unrestricted escape attests to the effectiveness of Pavlovian conditioning during avoidance response prevention in elevating CS aversiveness to a near ceiling level. 相似文献
16.
Svjetlana Kolić-Vehovec 《European Journal of Psychology of Education - EJPE》2002,17(2):129-138
The effect of the self-monitoring training on reading accuracy and fluency of second-grade poor readers was examined. The participants were assigned in one experimental and three control groups. The experimental group was reinforced with token-economy for self-correction and fluent reading. One control group practiced reading without feedback, the second one practiced the calculation of simple arithmetic tasks, and the third one received no training at all. The improvement in reading accuracy was obtained only in the self-monitoring group, and remained for five months. However, the improvement in reading fluency was obtained in the two reading groups, but only the self-monitoring group showed further improvement during five months after training. The results confirmed the importance of self-monitoring already at the level of lexical access in reading and that of local text comprehension. 相似文献
17.
This study examined the impact of direct instruction and interactive instruction on immigrant kindergarten children’s vocabulary learning during storybook reading. (In the present study the terms “immigrants” and “second language learners” are used alternatively meaning kindergarteners from immigrant families who are in the process of acquiring a second language besides their mother tongue.) Eighty seven immigrant kindergarten children, aged 4–6 years old (mean = 61.68 months, standard deviations = .51) were recruited from 12 public kindergarten classrooms located in Crete. Children were acquiring Greek as a second language. The immigrant children of the 12 kindergarten classrooms were randomly assigned to two experimental groups and one control group. During the intervention phase, six stories were read twice in whole group settings. Target and non-target words were assessed by multiple choice vocabulary measure before and after the storybook readings. In the first experimental group, children were provided brief explanations of target words by direct instruction. In the second experimental group, children were involved actively in discussing target words according to interactive instruction techniques. In the control group stories were read without any explanation of target vocabulary. Results showed that interactive instruction was more beneficial on target vocabulary learning than direct instruction and the impact was greater for instructed words than for uninstructed ones. In addition, results showed that boys and girls responded differently to the teaching procedures. Specifically, in both conditions where teaching procedures were implemented, girls outperformed boys on instructed words. Furthermore, children’s initial level in Greek receptive vocabulary and target word knowledge had a significant impact on target word learning. 相似文献
18.
In two predictive-learning experiments, we investigated the role of the informational value of contexts for the formation of context-specific extinction learning. The contexts were each composed of two elements from two dimensions, A and B. In Phase 1 of each experiment, participants received acquisition training with a target cue Z in context A1B1 (the numbers assign particular values on the context dimensions). In Phase 2, participants were trained with conditional discriminations between two other cues, X and Y, for which only one of the two context dimensions was relevant. In a third phase, participants received extinction trials with cue Z in context A2B2. During a final test phase, we observed that a partial change of the extinction context disrupted extinction performance when the extinction context was changed on the dimension that had been trained as being relevant for the conditional discrimination. However, when the extinction context was changed on the irrelevant context dimension, extinction performance was not affected. Our results are consistent with the idea that relevant contexts receive more attention than do irrelevant contexts, leading to stronger context-specific processing of information learned in the former than in the latter type of contexts. 相似文献
19.
In the first experiment, a prolonged period of intermittent, unsignaled shocks preceded appetitive runway acquisition, under either continuous (CRF) or partial reinforcement (PRF) and extinction. In the second experiment, the shock treatment came between CRF or PRF acquisition and extinction; and in the third experiment, the shocks intervened between appetitive CRF acquisition and shock-punishment extinction. The main finding was that compared with an unshocked control, shock facilitated acquisition in Experiment 1, and led to increased resistance to extinction and/or punishment in all experiments. In Experiment 1, the shock effect in appetitive extinction was seen mainly in the CRF group; in Experiment 2, the effect was to increase persistence in both the CRF and PRF groups; and in Experiment 3, shock treatment produced stronger resistance to punished extinction. The discussion is in terms of habituation and a general theory of persistence, and the concept of helplessness. 相似文献
20.
目的:研究肺康复对稳定期COPD患者肺功能、运动耐力的影响。方法:选择稳定期COPD患者100例,随机分为对照组和实验组,两组患者在常规内科药物治疗的基础上分别接受单模式肺康复和综合性肺康复。训练前及训练后1个月、3个月、6个月及1年评定患者的肺功能指标和六分钟步行距离,并用独立样本t检验、重复测量方差分析及Pearson’s相关系数对结果进行统计学分析。结果:两组患者的肺功能指标在治疗后1个月、3个月与治疗前比较,无明显差异,治疗后6个月和1年则较治疗前有显著差异;六分钟步行距离治疗后1个月与治疗前比较无明显差异,治疗后3个月、6个月和1年则较治疗前有显著差异,且实验组患者的各项指标明显优于对照组,同时六分钟步行距离与肺功能指标之间存在相关性。结论:单模式肺康复和综合性肺康复均能改善COPD患者的肺功能和运动耐力,但综合性肺康复治疗方案优于单模式肺康复,且康复训练具有时间依赖性及累积效应,需长期坚持才能见效。 相似文献